Key lock



Patented ll, l9IZ5 lySeSLZD' CHARLES T, STEPHENS, OF CHICGQ ILIJINOEIS.

KEY LOCK.

Application filed May 1.2, 1924..

To all whom t may concern Pye it known that l, @Hannes T. STEPHENS, acitizen of the nited Statesy residing at 'Chicago l-lcights.` in thecounty oit Cook and l@tate ot illinois, have invented new and usetulimprovements in Key flocks7 ot which the hillowing is a specification.

rlhis invention relates to new and use'tul' improvements in piano keylocks and more articularly to a device of this character which isparticularly adapted 'for use upon a player piano whereby to lock thekeys against movement when so desired. rlhe main object of the presentinvention is the provision ot an extremely simple and ine):- pensivedevice which may be quickly and readily applied to any well known makeof player piano and adjusted tor use -in lockingj the keys ot the keyboard against move ment when so desiredq during? the pla` no ot theinstrument.

Another object of the present invention is the provision of a device'tor locking the keys oi a key board in a player piano w lich can bequickly and readily installed? and the operating',mechanism thereoit isentirely out et sie'lif; the only visible portion ot the mechanismbeing1 the foot operated treadle which actuates the device for lockingor unloekineB the keys oit the key board.

ltr/lith the above and other objects in view the invention consists inthe novel features in constructiom the combination and rangement ofparts hereinafter more tully set forth, pointed out in the claims andshown iu the accompanying drawings in which Fie. 1 is a top plan view ofa piano key board illustrating; the application ot my improved lock.

Fig'. 2 is a longitudinal sectional view taken on the line 2--2 of Figi.l.

l" 3 is a transverse sectional view taken on the line 3--3 of Fig. 2.

l is an elevation as indicated at lt-4 ot Fig. 3.

5 is a transverse sectional view taken on the line 5 5 ot Fig. 3.

Referring more particularly to the drawinpjs the numeral l indicates thekey board ot an ordinary player piano, the keys ot the board being'supported for pivotal movement upon the center support 2. Arranged abovethe key board and extending transversely ot the keys at a point adjacentthe inner ends .est is a o7 the ends Serial No. ?l2,743.

ot which are provided with suitable opento receive the `guide bolts 4which are fied by the supporting shelt14 5 ot the key board and mountedupon these bolts are cuitable coil springs 6, the tension ot which normally moves the locking' bar 3 upwardly arrakisJ the nuts 7 threaded uponthe upper ends et said bolts. thus when thc locking; bar is released thesprings 6 will have a tendency to Ytorce. the bar 3 upwardly and releasethe keys ot the key board.

li connecting: link 8 is attached to the central portion of the locking;bar 3 and the lower end thereof is detachably connected to the centralportion ot a longitudinal shaft 9, the ends ot which are mounted withinsuitable e'uides l0 to permit lateral movement ot the shaft, The shaft 9is connected to the upper end o? a rod il by suitable loose connectionl2 and the lower end of this rod is provided with a sleeve 18 adapted toembrace the crank arm lli ot the operating shaft The operating` shaft l5is extended transversely o'li the key locking' bar 3 and shaft 9 and ismounted for rotation in suitable hearings 16, the crank 14; beine;disposed het*v een these bearings and attached to the cuter end et theshatt l5 is a toot tig'eedle 17 which is extended equally upon oppositesides ot the shaft.

,tts noted in Fig'. 3 the outer end oit the shaft xrirojects beyond theforward wall of the piano easing' 18 and the toot treadle 17 ispositioned upon the outer end of the shaft au. shown in this ligure.

As shown in 8 the locking;- bar 3 has been moved downwardly against theupper surfaces ci the key members of the key board to retain them in alocked position and the relative position of the crank 14.- is clearlyillustrated in Fig'. 2 with the bipght portion of the crank disposedslightly beyond the gravity center ot the same so as to securely retainthe bar 3 aggainst the tension of the spring 6 so that when the crank isreleased to its unlocked position the tension of the spring will readilyraise the bar to release the keys.

In order to limit the swinging movement of the crank member 14 a stoparm 19 is attached to the shaft l5 ata point adjacent the crank, saidarm having its outer end slightly turned as at 2O to form an engaeinpportion4 adapted to rest upon a stop 21 tixeto the bottom of the' pianocasing so as to prevent outer end. ot the arm ronrr

